In Matthew 16:6 Jesus says to the disciples: “Watch out, and beware of the yeast of the Pharisees and Sadducees.”

If that statement leaves you a little baffled, it is encouraging to note that the disciples were baffled, too. And they said among themselves, ‘It is because we have not brought any bread.’ This is rather like listening to Einstein talking about his Theory of Relativity and deducing that he’s talking about his aunts and uncles. You can almost see Jesus rolling his eyes: “You have so little faith, why are you talking among yourselves about having no bread? Do you still not understand”

What was Jesus getting at? Anyone who has ever made bread will tell you that a little yeast is enough to make a whole batch of dough rise. Just a little of it affects everything.

And now swap the word “yeast” for the “word “attitude” and you see the point easily enough. Just a little of the attitude of those people affects everything, corrupts everything. Jesus cites two different –opposite- religious attitudes and says that either of them, even in a minimal dose, can poison one’s whole perspective.

Don’t forget that the Pharisees were not’ bad people’ per se. Indeed, they were concerned, committed followers of God. However, they did tend to think that they had “got it” and that, consequently, no one else had. This is the very heart of fundamentalism: it is the attitude that says only those who believe and behave like us are saved, everyone else is damned or at least of no consequence.

Of course, you don’t have to be a Christian to be a fundamentalist! The secular equivalents of fundamentalism are everywhere at work. The yeast of the Pharisees makes people more concerned about who is ‘in’ and who is ‘out’ that just trying to get on and do the will of God. It makes people continually define themselves over against others. Pharisees are big on walls.

The “yeast of the Sadducees” is an opposite tendency. The Sadducees were the ruling religious elite, collaborating closely with Roman power. To maintain that power, the status quo must be carefully kept, since that feathered their own nest. Ultimately, then, they were not committed to God so much as to their own position, but they did have considerable religious power and used that to maintain things the way they liked them. They were prepared to go along with more or less anything so long as their world didn’t change. In the course of that maintenance, vital elements of their own faith were quietly accommodated to the secular power. In Brother Yun’s classic Heavenly Man he describes the temptation of the Chinese house-church movement to join the official state-run church. Just sign here and all persecution will be at an end. But this was “the yeast of the Sadduccees” and he refused to swallow it.

So Jesus said “Beware of both those attitudes because they will poison you completely.” Did you hear it?

Religious intolerance will wall you up into defensive positions and shut everybody else out.

Secular tolerance will dilute you until you become tasteless. What good is salt that has lost its flavour?

As I just said, fundamentalism is a human attitude, not a Christian preserve. But the terrible irony for those who would call themselves Christians, however, is the situation we often encounter, where in the name of Jesus (“Love one another!” “Love your enemies!” “I do not condemn you…”), anyone who is unwilling to conform to a narrow creed of sharply defined beliefs is cheerfully consigned to the hell of the outsider, to “darkness and gnashing of teeth.”

As I write, here in the Republic of Ireland, we watch the TV reports of the annual 12th July marches in Belfast. Nights of rioting, darkness and blood. Political tribalism meets religious fundamentalism. Again.

So much done in the name of Jesus. Or in the name of Allah. Or in the name of “this great country” (whichever your’s is…).

The problem here is what such attitudes do to the individual’s personality and how they misrepresent the true spirit and intention of Christ’s teaching. The desire to exclude others has continually bedevilled the human race, but when it masquerades as religion, indeed as the only true religion, it becomes deadly, and we hear too much about religious intolerance to be in any doubt about that.

Probably for most western Christians, however, the bigger temptation is to be leavened by “the yeast of the Sadducees”. While some Christians make themselves clearly, aggressively different to everyone else, many of us live and think in a way that is scarcely distinguishable from our unbelieving neighbours. We practise our religion quietly and discretely, but we don’t let it frighten the horses, don’t let it in any way make us seem strange or out of step with the rest of the world. All too easily, Christianity becomes something tacked on to the end of our lives, rather than the organising principle, the driving force of our lives. The Sadducees were in one sense the most Jewish of people, they could trace their ancestry back to the time of Solomon, but their religion was comfortable and static, in no way a force for transformation. If we adopt their attitude, our faith does nothing to change us or make us grow in the likeness of Christ, which is its real purpose. In fact, unlike the yeast of the Pharisees, the yeast of the Sadducees is not something people consciously adopt; it’s something they just slip into, it’s the obvious way to be, just to go along with the way things are.

The Christian is called to be passionately committed to Christ while remaining open to others, and to be open to others without simply accepting anything and everything.

But what is “the way things are”?

Clearly, Westernised culture has a few motivating principles that form the “yeast of the Sadducees.” It’s really hard to steer clear of the pull of that current, since it flows like a Tsunami through our media outlets, our education system, our political hierarchies…pretty much everything that makes up our society.

To say it as simply and clearly as possible, Jesus came to announce to us that an identity based upon success, popularity and power is a false identity- an illusion! Loudly and clearly he says: ‘You are not what the world makes you; but you are children of God.”

Even our spiritual experience falls prey to the governing “yeast” of our culture: it becomes so individualized that concepts such as “a contrite heart,” have come to refer only to the personal experiences of guilt and willingness to do penance for it. The awareness of our impurity in thoughts, words and deeds can indeed put us in a remorseful mood and create in us the hope for a forgiving gesture. But if the catastrophical events of our days, the wars, mass murders, unbridled violence, Guantanamo Bays, famine, AIDS and the unnameable misery of most of the world is safely kept outside the solitude of our hearts, our contrition remains no more than a pious emotion.

And yet, within this tide of culture, the greatest trap in our life is not success, popularity, or power, but self-rejection. Success, popularity, and power can indeed present a great temptation, but their seductive quality often comes from the way they are part of the much larger temptation to self-rejection. When we have come to believe in the voices that call us worthless and unlovable, then success, popularity, and power are easily perceived as attractive solutions. The real trap, however, is self-rejection. As soon as someone accuses me or criticizes me, as soon as I am rejected, left alone, or abandoned, I find myself thinking, “Well, that proves once again that I am a nobody.” I am tempted to think I am no good, that I deserve to be pushed aside, forgotten, rejected, and abandoned.

That one thing- Being loved– constitutes the core truth of our existence. That is the yeast of Jesus: the identity of one fully awakened to the thrill of being human, being alive. And to this one tiny seed-principle, Jesus committed the changing of the world.